REDMOND, Wash.— June 25, 2012 — Microsoft CEO Steve Ballmer, Yammer CEO David Sacks and Microsoft Office Division President Kurt DelBene will hold a press teleconference June 25, 2012, at 11:30 a.m. PDT to announce that they have entered into a definitive agreement under which Microsoft Corp. will acquire Yammer Inc., a leader in enterprise social networking, for $1.2 billion.

Teleconference Information

Toll-free dial-in: (800) 779-0714

Toll dial-in: (517) 308-9332

Passcode: 4460902

A moderated Q&A will follow prepared remarks by Ballmer, Sacks and DelBene. No additional interviews will be granted.

A transcript of the prepared remarks from the teleconference will also post to the Microsoft News Center upon completion of the call.

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